Objective: To study the clinical value of breast multimodal imaging in evaluating axillary lymph node (ALN) and internal mammary lymph node (IMLN) metastases of breast cancer. Methods: A total of 1000 patients with breast cancer who were diagnosed and treated in the Huichang County Maternal and Child Healthcare Hospital and the Breast Disease Diagnosis and Treatment Center of the First Affiliated Hospital of Gannan Medical College from January 2020 to December 2023 were selected. All patients underwent sentinel lymph node (SLN) biopsy and breast multimodal imaging based on functional magnetic resonance imaging (MRI), contrast-enhanced ultrasound and mammography. According to the results of SLN biopsy, the patients were divided into metastasis group and non-metastasis group. General information and multimodal imaging results of the two groups were compared. Multivariate logistic regression model and the receiver operating characteristic (ROC) curve were used to analyze the diagnostic value of multimodal imaging for ALN and IMLN metastases of breast cancer. Results: There were significant differences in the maximum diameter, clinical stage, histological grade and molecular subtype of primary lesions between the two groups (P<0.05). Multivariate analysis showed that the maximum diameter, clinical stage, histological grade and molecular subtype of the primary lesion were independent risk factors for ALN and IMLN metastases in patients with breast cancer (P<0.05). The area under the curve of joint prediction using the four indicators was 0.900, which was greater than that of each indicator. The sensitivity and specificity of joint prediction were 92.31% and 77.78%. Conclusion: Multimodal imaging has high value in evaluating ALN and IMLN metastases in patients with breast cancer.